Field of the Invention
The present invention relates to a hybrid vehicle that is equipped with an engine and an electric motor as power sources and that is capable of selecting between an electric traveling mode (EV mode) that travels only by an electric motor and a hybrid traveling mode (HEV mode) that travels by the electric motor and the engine.
Background Information
For example, a hybrid vehicle such as that disclosed in Japanese Laid-Open Patent Application No. 2000-199442 has been known. In this hybrid vehicle, the engine is detachably coupled with driving wheels sequentially via a continuously variable transmission and a clutch, and an electric motor is constantly coupled with the driving wheels. The hybrid vehicle further comprises a mechanical oil pump that is driven by the engine and that supplies oil to the continuously variable transmission and the clutch.
This hybrid vehicle is capable of electric travel (EV travel) in the EV mode via only the electric motor by stopping the engine, as well as by releasing the clutch described above, and is capable of hybrid travel (HEV travel) in the HEV mode via the electric motor and the motor by starting the engine, as well as by engaging the clutch.
Since the engine and the continuously variable transmission are disconnected from the driving wheels by releasing the clutch during EV traveling, the friction of the engine and the continuously variable transmission can be reduced during EV travel.